Dictionary Override - Reference Qualifier Question

[Lucky1]

Hello all,

Good day!!

On the Incident form, when a configuration item is selected from "Mapped Application Service" (cmdb_ci_service_discovered) class, then only their related Services has to be shown for selection in the "Service" (business_service) field, but not all services. 
For this I have written a Script include, but 

the problem here is, when I open the "Service" field on the dictionary level, I see there is a Dictionary Override, on the Incident. and that is oob one.

javascript:new TaskUtils().getConfigurationItemFilter(current);

Now without disturbing the existing functionality, I want to include my script include results also to this reference qualifier, like if(sys_class_name == 'cmdb_ci_service_discovered'), 

My Script Include:

var Incident_cmdb_Utils = Class.create();

Incident_cmdb_Utils.prototype = {

    initialize: function() {},

    getServicesForCI: function(ciSysId) {

       // var ciSysId = this.getParameter('sysparm_ci_sysid');

        gs.log("Results are Configuration item sys_id " + ciSysId);

        var serviceIds = [];

        if (!ciSysId) {

            return serviceIds;

        }

        // Step 1: Find offering(s) where child = selected CI (Mapped Application Service)

        var offeringGR = new GlideRecord('cmdb_rel_ci');

        //offeringGR.addQuery('child', ciSysId);

        //offeringGR.addQuery('parent.sys_class_name', 'service_offering');

        offeringGR.addEncodedQuery('parent.sys_class_name=service_offering^child.sys_id=' + ciSysId);

        offeringGR.query();

        while (offeringGR.next()) {

            var offeringId = offeringGR.parent.toString();

            gs.log("Results are Inside 1st While " + offeringId);

            // Step 2: For each offering, get parent services (business or technical)

            var serviceGR = new GlideRecord('cmdb_rel_ci');

            // serviceGR.addQuery('child', offeringId);

            // serviceGR.addQuery('parent.sys_class_name', 'IN', 'cmdb_ci_service_business,cmdb_ci_service_technical');

            serviceGR.addEncodedQuery('parent.sys_class_name=cmdb_ci_service_business^ORparent.sys_class_name=cmdb_ci_service_technical^child.sys_id=' + offeringId);

            serviceGR.query();

            while (serviceGR.next()) {

                //  gs.log("Results are Inside 2nd While");

                serviceIds.push(serviceGR.parent.toString());

                gs.log("Results atLast are " + serviceIds); //some duplicate sys_ids are coming here

            }

        }

        // return serviceIds;

        return JSON.stringify(serviceIds);

    },

    type: 'Incident_cmdb_Utils'

};

So, can someone please help me here?

Regards,

Lucky